Millstone-driver



I 2 Sheets-Shee'ti. W. JOHNSON.

Millstdne-Drivr; 7 No. 224,291. Patented Feb. 10, 1880.

W MI H 2 I 2 Sheets-Sheet W. JOHNSON.

Millstone-Driver. e

No. 224,291. Patented Feb. 10,1880.

w woe ensues "PETERS, PHOl'D-LITMOGRAPKER. WASHINGTON D C oNir-TEe-s-TmsPATENT OFFICE.

MILLSTONE'DRIVER.

SPECIFICATION forming part of Letters Patent No. 224,291,

' Application filed November 21, 1878.

' To all whom it may concern:

Be it known that 1, WILLIAM JOHNSON, of Milwaukee, in the county ofMilwaukee and State of Wisconsin, have invented certain new and usefulImprovements in Millstone-Drivers and I dohereby declare the followingto be a full, clear, and exact description thereof, reference being hadto the accompanying drawings,-

and to the letters of reference marked thereon. The nature of myinvention consists in the construction and arrangement of amillstonedriver whereby a millstone may be run true and even, so as tomake good and uniform flour, as will be hereinafter more fully setforth.

In order to enable others skilled in the art to which my inventionappertains to make and use the same, I will now proceed to describe itsconstruction and operation, referring to the annexed drawings, whichform a part of this specification, and in which Figure 1 is aperspective view of my improved millstone-driver with cap partiallyremoved. Fig.2 is a side view, and Fig. 3 a central vertical section, ofthe same. Fig. 4. is a plan view of the bed of the driver. Fig. 5 is aplan view, partly in section, of the link and pivoted jaws. Fig. 6 is aplan view of the entire driver.

A represents the bed of the driver, constructed substantially in theform shown in Fig. 4, and formed witha central opening, a, for thepassage of the mill-spindle. Around this opening is a raised rim orflange, c, and in the center, at the outside, and each endof this flangeis a raised projection, B, for the.

over the projections B, with their wooden side bearings, D D; To thelink E are pivoted four jaws, F, by means of pins G, which admit of said'jaws turning or oscillating up'and down for a limited distance, forthepurpose of allowing the stone to be kept even. Each jaw F is providedwith a facing, .11, suitably dated February 10, sso.

formed by said jaws and the links are inserted rubber strips I, whichform elastic or yielding cushions. At the point where the link rubsagainst the wooden bearings D suitable brass facings are to be fastenedto the link.

M is a cap or top plate fitting around the upper partof the rim 0, andfastened to lugs upon the projections B of the bed A for holding theparts'in place.

The mill-spindle passes up through the opening a in the bed of thedriver and fits therein, so that the driver will turn with the spindle.The jaws F are to fit over the ends of the ordinary hail of the stoneand come in contact therewith. The link may move in either direction, soas to bear against the bail and drive the stone. If the spindle shouldbe out of tram, the two operating-jaws will turn on their pivots topresent flat surfaces against the sides of the bail and permit the stoneto run parallel with the bed-stone.

It will readily be understood that when the will be in contact with thebailthat is, the upper edge on one side and the lower edge on the otherside; but by constructing the jaws so as to be capable of rocking theywill adjust themselves, and their entire surfaces will rest flat againstthe sides of the bail. The elastic or yielding cushions interposedbetween the jaws and link are to prevent any vibration or tremble thatotherwise would occur, and also to facilitate the action and adjustmentof the pivoted jaws in their movement on the bail to accommodate thecookingof the stone.

'I am aware that a millstone-driver has been devised having aslidinglink or yoke, provided with pivoted drag-levers linked to the bail, soas to permit automatic adjustment between the stone anddriver toaccommodate that a driver has been devised wherein a sliding link oryoke has been provided with arms fitting up into'the bail, said armshaving elastic cushions covered by convex disks, the disks and cushionssecured to the arms by horizontal pins; and do not claim such devices,the firstnamed being objectionable because there is no provision forbacklash or reverse driving. It is limited in its'capacity to permitautomatic adjustment between the driver and stone, and

the tilting or cocking of the stone; and also it does not apply thepower to the best advantage. And the second mentioned is objectionablebecause it depends for its driving contact and adjustment on a convexface, which gives 5 little frictional contact, and is liable to wear theface of the bail irregularly; and, finally, both forms are objectionablein that they demand a special construction of bail adapted to thepeculiar form of each driver.

10 Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is-

1. In a millstone-driver, the sliding link or yoke provided withhorizontally-pivoted ver- 15 tically-oscillating jaws, whereby acompound

